.main{
    min-height:600px
}
.fr{
  float: right;
}
.article-title{
  font-size: 24px;
  font-weight: bold;
}
.tl{
  text-align: left;
}
.tc{
  text-align: center;
}
.tr{
  text-align: right;
}
.mr-20{
  margin-right: 20px;
}
.index-title{
  font-size: 36px !important;
  font-weight: bold;
}